Reversible ratchet mechanism



Oct. 25, 1949. c. w. LOFGREN REVERSIBLE RATCHE'I' MECHANISM Filed April 12, 1946 fire/afar Car} ZO IjVI-WJ Z fl/orm .y

Patented Oct. 25, 1949 UNITED STATES PATENT OFFICE 1 Claim.

My invention relates to tools and more particularly to screw drivers.

The object of my invention is to provide a screw driver having a flexible shank, so that it can be used for driving screws or manipulating nuts in spaces which would make it difiicult to use common screw drivers.

Another object of my invention is to provide a screw driver having a flexible shank which is provided with a reversible ratchet handle to make it possible to tighten or untighten screws or nuts.

Other objects of my invention may appear in the following specification describing m invention with reference to the accompanying drawing illustrating a preferred embodiment of my invention. It is however to be understood that my invention is not to be limited or restricted to the exact construction and combination of parts described in the specification and shown in the drawing, but that such changes and modifications can be made, which fall within the scope of the claim appended hereto.

In the drawing:

Figure l is an elevational view of a screw driver according to my invention, a part of the flexible shank being shown as broken away and a part of the handle being shown in section.

Figure 2 is a partial vertical sectional View through the ratchet housing on the lower end of the handle.

Figure 3 is a sectional view taken on line 3-3 in Figure 2, and

Figure 4 is a sectional View taken on line 4-4 in Figure 2.

Referring now to the drawing in detail the tool according to my invention has a handle in in which a hole is provided adapted to receive a metal tube I l.

The tool has a shank consisting of an outer tightly wound helical spring [2 and an inner helical spring l3. One of said springs is wound in clockwise direction and the other one in counter-clockwise direction.

The metal tube H is firmly held in the handle I and serves as a bearing for the upper end of the flexible shank.

Adjacent the lower end of the shank a short metal tube I4 is slidably and rotatably mounted on the shank and serves as-a finger grip to hold the tool in working position relative to the work. On the lower end of the flexible shaft a square or hexagon-shaped head I5 is rigidly mounted and is adapted to be seated in a complementary socket part IS, a screw driver I! or like tool. Head I5 may be detachably connected to socket It by a conventional ball latch or the like.

While a screw driver I! is shown in the drawing, it is to be understood that other tools can be attached, for instance socket wrenches of various sizes or the like.

On the lower end of the handle ID a housin I8 is attached and serves as a ferrule to th handle.

The fiexible shank extends rotatably through the housing I8. An end thrust bearing H! for the shank is located inside the housing resting on the bottom thereof. Just above this bearing a ratchet wheel 20 is rigidly mounted on the shank. A spring 2| preferably made from straight tempered spring steel is fastened to the inside of the housing l8 by means of a rivet ,22 or the like. It is arranged on the same transverse plane as the ratcher wheel 20 and partly surrounds the same. The free end of the spring is bent inwardl as shown at 22 to provide a pawl.

A washer or spacer 23 is located above the ratchet wheel 20 and surrounds the shank and on top of this spacer a ring 24 is arranged around the shank. A lever 25 extends radially and outwardly from this ring and is integrally formed therewith. It extends through a horizontally arranged slot 26 in the circumferential wall of the housing l8. Inside the housing a curved shield 2'! is rigidly attached to the lever and closes the slot 26. The lever can be pivoted about the shank to the extent of the length of the slot 26.

Inwardly of the shield 21 a slotted guide or retainer 28 is securely fastened to thelever 25 and extends above and below the lever.

In top of the lever ring 24 a second spacer '29 is arranged and just above this spacer a second ratchet wheel 30 is rigidly mounted on the shank. On the same transverse plane as the second ratchet wheel 30 a second spring 3| is firmly fastened on the inside of the housing H! by means of a rive't 32 and partly surrounds the second ratchet wheel 30. The tip end 33 of the second spring 3| is bent inwardly as shown in Figure 4 to comprise a pawl.

The two springs 2| and 3| extend through the slot in the guide 28. The teeth of the first ratchet wheel 20 are arranged to point in clockwise direction and the teeth of the second ratchet wheel 30 in counterclockwise direction.

The two springs 2| and 3| have the tendency to straighten out, that means to keep the respective tip ends out of engagement with the respective ratchet wheels. When the lever 25 is moved counterclockwise in Figure 1 so that it will be located in the position shown in Figure 3, the

guide '28 will force the tip end 22 of the first spring 2| into engagement with the first ratchet wheel 20 and will permit the tip end 33 to disengage the second ratchet wheel 30 so thatithe shank can be rotated by the handle 10 in counterclockwise direction and the handle can be rotated freely on the shank in clockwise direction. By moving the lever 25 in the position shown in Figure 4 spring tip, 22. will swing outwardly and spring tip.;33;will"beurged intogengagementwith the second ratchet wheel 30 so that the action will be in the opposite direction to the one described above.

Having described my inventiomliclaimi assn'ew and desire to secure by Letters Patent:.

In a tool having a shank and a handle freely rotatable on said shank, ratchet: meanst opera atively connecting said shank to said handle for rotating the shank in clockwise and counter= clockwise directions, said means comprising a ratchet wheel fixedly carried by-- saidshank, a:. second ratchet wheel" arranged above and spaced' carried by saidshank, a ring provided withanoutwardly projeoting leven rotatably' mounted on said shank intermediate said first'and seoondnamediratchet wheel's;- a:fiat' spring having anend secured to said handlc and having its other end so'sfor-medi as tor-provide a pawl, said: spring extending inas count'er clockwise direction about said": first -named ratchet wheel and having itspawl adapted to engage' the teeth of the latter wheel; a; second fiatspring having" an end secured to-saidhand-le and havingitsother end sowformed as to'= provide a pawl; said second-named" spring: extending' in I clockwise direction about said' sec-- ond-named ratchet wheel and having its pawl adapted to engage the teeth of the latter wheel, and a slotted guide secured to said lever and extending above and below the latter, each of said springs extending through said slotted guide, whereby actuation of the lever of the ring in one direction causes the guide to move the pawl of one of the springs into engagement with the teeth of one,of said. ratchet wheels. and. to move the pawl; ofi-I the; other-spring out of? engagement with the teeth of the other of the ratchet wheels to permit the rotation of the shank in a clockwise direction and actuation of the lever of the ring inztheioppositedirection causes the guide to move thepawLoi the other of said springs into engage- REFERENCES GIT-ED- Thev following references are of record inthe fi1e.ofithis patentz.

UNITED STATES PATENTS;

Number Name" Date FOREIGN PATENZFS Country Number" Date Cutter: Nov; 25,1913" Caruso Apr; 12', 1927- Miller. Dec: 10,1935

Great? Britain May-2,3; 1923- 

